Device for transfering electronic components from an inclined supply track to another element

ABSTRACT

Device for transferring electronic components ( 2 ) from a inclined gravity supply track ( 3 ) to another element, more particularly a receiving element ( 6 ), characterised in that it comprises at least one swing arm ( 14 ) fixed to an inclined rotating shaft ( 13 ) that is connected to driving means ( 15 ) and that is positioned between the supply track ( 3 ) and the receiving element ( 6 ), whereby the swing arm ( 14 ) forms an angle (C) with the rotating shaft ( 13 ) and is at least rotatable between a first position, whereby it is situated parallel to and above the supply track ( 3 ), and a second position whereby the swing arm ( 14 ) is situated above the receiving element ( 6 ), said device ( 1 ) further comprising suction means to suck up and to hold a concerned component ( 2 ) against the swing arm ( 14 ).

The present invention concerns a device for transferring electroniccomponents from an inclined supply track to another element like apacking element, a printed circuit board, a testing device or the like.

In particular, it concerns a device which can be used in tape-and-reelpackaging machines for successively transferring single electroniccomponents like semiconductors, IC's, and such, from an inclined gravitysupply track to a packing tape that is provided with pockets to holdsingle components and which is stepwise moved forward and sealed off, assaid electronic components are inserted one by one in said pockets,which packing tape is then wound on a reel.

Such tapes filled with electronic components are efficiently used forautomated assembly of printed circuit boards or the like.

In traditional tape-and-reel devices, said electronic components aretransferred from the inclined gravity supply track to the tape-and-reelmechanism, mainly by two types of pick-and-place devices.

A first type of known pick-and-place devices is formed by a single swingarm which is equipped with a vacuum nozzle that is pressed on the top ofthe electronic component to hold it. The electronic component is thenlifted from the supply track and moved over a pocket in the tape,following which the component is pushed into the underlying pocket andis released.

A second type of known pick-and-place devices is more complex and isformed by a rotary turret which is equipped with a single vacuum nozzleto pick up the electronic components from the supply track and to movethem to subsequent stations for inspection and transfer to a tape.

A disadvantage of these known pick-and-place devices is that theelectronic components are subjected to impact forces that can damage thecomponents, especially when new generation components, like for instancefragile thin shrink small components, have to be handled.

In these known pick-and-place devices the components are also exposed tolateral inertia forces that can cause the components to be misaligned onsaid vacuum nozzle, resulting in an incorrect positioning of thecomponent over a pocket. When the misaligned component is next pushedinto the pocket, the fragile leads are usually severely damaged and auseless component is sealed into the tape.

More recently, another kind of device has been introduced to transferthe electronic components from an inclined supply track to a tape. Thisknown device is formed by a rotating disk that is conicaly shaped, sothat at one side the disk is aligned to the supply track and that theopposing side of the disk is in a horizontal position. The electroniccomponents slide from the supply track into radial slots in the edge ofthe disk and are rotated to the opposite side, where they are picked upby a rotating pick-and-place mechanism to transfer them to a tape.

A disadvantage of this more recently known type of device is that theleads of the electronic components are in physical contact with saidrotating disk and are hence subject to be damaged. Another disadvantageis that an additional pick-and-place mechanism is, required that,moreover, can cause some damage to the components, concerned.

The invention aims to overcome the aforementioned and otherdisadvantages.

To this aim, the invention concerns a device for transferring electroniccomponents from an inclined gravity supply track to another element,more particularly a receiving element, characterised in that itcomprises at least one swing arm that is fixed to, or is part of, aninclined rotating shaft that is connected to driving means and that ispositioned between the supply track and the receiving element, wherebythe swing arm forms an angle with the rotating shaft and is at leastrotatable between a first position, whereby it is situated parallel toand above the supply track, and a second position whereby the swing armis situated above the receiving element, said device further comprisingsuction means to suck up and to hold a concerned component against theswing arm.

An advantage of the device according to the invention is that it allowsfor a very high throughput speed.

Another advantage is that no impact force from a pick-and-place arm isapplied to the electronic components eliminating all risks of damagingthe components and making it hence suitable to also handle more delicateelectronic components.

Yet, another advantage of the device according to the invention is that,due to the smooth controlled rotation of the swing arm, the electroniccomponents keep their correct position on the swing arm, so that theyare always correctly positioned in a pocket of the receiving element,hence avoiding costly system jams.

With the intention of better showing the characteristics of theinvention, several preferred forms of embodiment are describedhereafter, by means of example, without any limitative character, withreference to the accompanying drawings, wherein:

FIG. 1 schematically represents a device according to the invention;

FIG. 2 represents the device of FIG. 1 in a second position;

FIG. 3 represents a top view according arrow F2 in FIG. 1;

FIGS. 4 and 5 represent on a larger scale two cross-sections accordingto the respective lines IV-IV and V-V in FIG. 1;

FIG. 6 schematically represents a variant of the device of FIG. 1;

FIG. 7 schematically represents the device of FIG. 6, but withadditional visual inspection means.

FIGS. 1 to 5 represent a device 1 according to the invention fortransferring electronic components 2 from an inclined gravity supplytrack 3 which receives singular electronic components 2 from aninspection and supply compartment 4 of a packaging machine 5, to areceiving element 6, which, in this case, is a horizontally positionedpacking tape comprising a series of pockets 7 that are equally spacedalong the longitudinal direction of the tape and which can containindividual components 2.

The gravity supply track 3 extends in a vertical plane and is positionedfacing the exit where the electronic components 2 are released from theabove mentioned inspection and supply compartment 4.

It comprises two parallel fixed guiding profiles, respectively 8 and 9,which are positioned at a small distance apart and one above the other,and, which are inclined with an inclination angle A that, in the exampleshown, is an angle of 45°, but which can also have a different value.

The upper profile 9 contains in its bottom surface a longitudinalguiding groove 10 that is centred over the top of the lower profile 8.

The supply track 3 also contains an additional guiding profile 11 withthe same width as the lower profile 8 and which is parallel to it.

This additional profile 11 is connected to driving means 12 like anelectromagnet or such, and is movable in the plane of the supply track3, between a lower position and an upper position, whereby, in thisupper position, the upper surfaces of this movable profile 11 is alignedwith the upper surface of the fixed lower profile 8.

The device 1 according to the invention is installed between the supplytrack 3 and the above mentioned receiving element 6 and comprises aninclined rotation shaft 13 which is positioned in the same verticalplane as the supply track 3 and which carries a swing arm 14 which isfixed in an angle to the rotating shaft 13 and which is preferablydetachable.

The rotating shaft 13 is connected to drive means 15, like an electricalmotor or such, and is rotatable between a first position as representedin FIG. 1, whereby the swing arm 14 is situated above the supply track3, and at least a second position as represented in FIG. 2, preferablycorresponding to a rotation over 180°, whereby the swing arm 14 issituated above and across the receiving element 6.

The rotating shaft 13 and the swing arm 14 are preferably oriented insuch a way that, in said first position, the swing arm 14 is parallel tothe supply track 3, whilst in said second position, the swing arm 14 ismainly directed in a horizontal direction.

This is achieved by positioning the rotating shaft 13 and the swing arm14 in such a way that the inclination angle B of the rotating shaft 13and the acute angle C, formed between the swing arm 14 and the rotatingshaft 13, are both approximately equal to the value of a right angleminus half the value of the above mentioned inclination angle A of thesupply track 3. This is reflected by the expression B=C=(90°−A/2).

A longitudinal guiding groove 16 for the electronic components 2 isprovided in the bottom surface at the swing arm 14, whereby this groove16 is centred over the supply track 3 when the swing arm 14 is in itsfirst position and consequently forms in this position of the swing arman extension for the guiding groove 10 of the fixed upper profile 9 ofthe supply track 3.

The guiding groove 16 in the swing arm 14 is interrupted by a stop 17extending from the bottom surface of the swing arm 14.

The device 1 according to the invention comprises suction means formedby a vacuum device 18 that contains a suction port 19 that is connectedto the guiding groove 16 of the swing arm 14 by means of a hose 20 thatis connected to a tube 21 that extends through a passage hole 22 in theswing arm 14 and that communicates with said groove 16.

The above mentioned receiving element 6 is movable in its longitudinaldirection by means of a traction mechanism 23 that is for instanceformed by a traction wheel 24 with radial extending pins 25 thatco-operate with equally spaced perforations 26 in the rim of saidreceiving element 6 and that is fixed to the shaft of a driving motor27.

Control means 28 are provided to synchronise the movements of the abovementioned movable parts and are therefore connected respectively to therelease mechanism of the inspection and supply compartment 4; to thedriving means 12 of the movable profile 11; to the driving means 15 ofthe rotating shaft; to the vacuum device 18; and finally to the tractionmechanism 23 of the receiving element 6. These control means 28 are wellknown by a person skilled in the concerned technical field and aretherefore not further described in detail in the present application.

The operation of the device according to the invention is very easy andas follows.

The electronic components 2 are released one by one by the control means28 from the inspection and supply compartment 4 and are fed between thefixed upper and lower profile 8-9 of the supply track 3.

When an electronic component 2 is released, the movable part 11 of thesupply track 3 is situated in its upper position and the swing arm 14 issituated in its first position. This situation is represented in FIG. 1and corresponds to a situation where the movable profile 11 forms anextension for the lower fixed profile 8 and where the guiding groove 10of the swing arm 14 is aligned with the guiding groove 16 of the fixedupper profile 9 of the supply track 3.

It is clear that the released component 2 will slide down by gravity,being supported at the bottom surface of its body 29 by the guidingprofiles 8-11 and being guided at its top by the guiding grooves 10-16of the upper profile 9 and of the swing arm 14, in such a way that theleads 30 of the component 2 are freely suspended on both sides of theprofiles 8-11 of the supply track 3 and are not in contact with any partof the device 1. The width W of the profiles 8-11 is therefore smallerthan the distance D between opposite leads 30 of the component 2.

When the component 2 reaches the above mentioned stop 17, the vacuumdevice 18 is activated by the control means 28 so that the component 2is sucked up in the guiding groove 16 and is strongly held against theswing arm 14.

Once the vacuum device 18 is activated, the movable part 11 of thesupply track 3 is moved to the lower position at a safe distance fromthe leads 30 of the component 2, so that, during a next step, when thecomponent 2 is transferred by rotation of the swing arm 14, the leads 30are kept clear of the supply track 3 to avoid possible damage to theleads.

The swing arm 14 is next rotated to its second position, as representedin FIG. 2, so that the electronic component 2 is transferred to aposition exactly above a pocket 7 of the receiving element 6.

The vacuum device 18 is then deactivated by the control means 28, sothat the electronic component 2 is released and is dropped into saidpocket 7 from a very small height.

Next, the traction mechanism 23 is activated and the receiving element 6is moved over a distance corresponding to the centre distance betweentwo successive pockets 7 and the newly filled pocket 7 is simultaneouslysealed off by a tape which is not represented in the drawings.

At the same time, the swing arm 14 is rotated back to its first positionand the movable part 11 of the supply track 3 is raised again to alignwith the lower profile, so that the situation, as represented in FIG. 1,is again obtained.

Next, a following component 2 is released from the supply compartment 4to be transferred to the receiving element 6 in a similar way as alreadyexplained.

Preferably the empty receiving element 6, more specifically the packingtape, is unwound from a first reel which is not represented in thedrawings, whilst the filled and sealed packing tape is wound on a secondreel which is also not represented in the drawings.

Another embodiment of a device according the invention is represented inFIG. 6, whereby a second swing arm 14 is fixed to the rotating shaft 13in a symmetrical way with respect to the first swing arm 14 and wherebythis second swing arm 14 is also connected to the vacuum device 18.

It is clear that in this case, for the same speed of the rotating shaft13, the speed of transferring electronic components 2 is doubled becausea component 2 can be picked up by one swing arm 14 at the same time as apreviously picked component 2 is released over a pocket 7 of thereceiving element 6 by the other swing arm 14.

In yet another embodiment three swing arms 14 are fixed to the rotatingshaft 13 under three identical angles.

In FIG. 7 yet another embodiment of the invention is represented,whereby, in respect to the previous embodiment, a visual detectiondevice 31 with a detection camera 32 or the like has been added, whichcamera 32 is positioned right on top of the pocket 7 which has to befilled next.

The visual detection device 31 is connected to the control means 28 tomonitor the movement of the receiving element 6 in such a way that theconsecutive pockets 7 of the receiving element 6 are always stopped atexactly the same centred position right underneath the swing arm 14 whenit releases a component 2, compensating in this way for possibletolerance differences in spacing and dimensions of the pockets 7.

The visual detection device 31 also monitors the correct positioning ofthe electronic components 2 in the pockets 7 and the packaging processis stopped as soon as a positioning problem is detected, so that anoperator is able to remove the misplaced component 2 before the pocket 7is sealed off.

An important advantage of the present invention is that the detectioncamera 32 can be placed above the pocket 7 which has to be filled next.This is not possible for existing packaging machines where thepick-and-place device is already on top of this spot, so that usuallythe detection camera is installed in a more downstream position whereincorrectly positioned components 2 can only be detected after they havebeen sealed in. Also, in this case, monitoring of the correctpositioning of the concerned pocket 7 to be filled is not very accuratebecause monitoring is done on another downstream pocket 7.

The present invention is in no way limited to the forms of embodimentdescribed by way of example and represented in the figures, however, onthe contrary, such device for transferring electronic components may berealised in various forms and dimensions without leaving the scope ofthe invention.

1.- Device for transferring electronic components from an inclinedgravity supply track to another element, for example a receivingelement, comprising at least one swing arm fixed to an inclined rotatingshaft that is connected to a driving means and that is positionedbetween the supply track and the other element, wherein the swing armforms an angle with the rotating shaft and is at least rotatable betweena first position, whereby it is situated parallel to and above thesupply track, and a second position whereby the swing arm is situatedabove the other element, said device further comprising a suction devicearranged to suck up and to hold a respective component against the swingarm. 2.- Device according to claim 1, wherein the inclination angle ofthe rotating shaft and the acute angle formed between the swing arm andthe rotating shaft are both approximately equal to the value of a rightangle minus one-half the value of the inclination angle of the supplytrack. 3.- Device according to claim 2, wherein the inclination angle ofthe supply track is 45° and the inclination angle of the rotating shaftand the angle formed between the swing arm and the rotating shaft areboth equal to 67°30′. 4.- Device according to claim 1, wherein theinclined supply track contains at least one guiding profile that cansupport a respective electronic component at the bottom surface of itsbody. 5.- Device according to claim 4, wherein the width of said guidingprofiles that can support a respective electronic component is smallerthan the distance between opposite leads of the components to betransferred. 6.- Device according to claim 4, wherein at least a part ofsaid supply track is movable. 7.- Device according to claim 1, whereinthe swing arm contains in its bottom surface a longitudinal guidinggroove for the electronic components, wherein this guiding groove iscentered above the supply track when the swing arm is situated in saidfirst position. 8.- Device according to claim 7, wherein the guidinggroove in the swing arm is interrupted by a stop. 9.- Device accordingto claim 7, wherein that said suction device comprises at least a vacuumdevice which is connected to the guiding groove in the swing arm nearbysaid stop. 10.- Device according to claim 1, comprising two similar onesof said at least one swing arm which are symmetrically fixed to therotating shaft. 11.- Device according to claim 1, comprising threesimilar ones of said at least one wing arm which are ficed to therotating shaft at three indentical angles. 12.- Device according toclaim 9, wherein the electronic components are supplied one by one by arelease mechanism; the other element is a receiving element that is apacking tape that is moved by a traction mechanism; and furthercomprising a control system that is connected to said release mechanism,to the driving means of the supply track, to the driving means of therotating shaft, to the vacuum device, and to the traction mechanismassociated with the receiving element. 13.- Device according to claim12, wherein said control system additionally includes a visual detectiondevice with a camera which is positioned above the receiving element ata position above the corresponding second position of the swing arms.